title: Cataracts among adults aged 30 to 49 years: a 10-year study from 1995 to 2004 in Korea.
abstract: OBJECTIVE
  To investigate the long-term characteristics of cataracts among adults aged 30 to 49 years in Korean over a span of 10 years.
  
  
  METHODS
  Subjects between the ages of 30 to 49 years who underwent cataract surgery at St. Mary's Hospital from 1995 to 2004 (n = 976) were included. Patients with a history of ocular trauma, uveitis, other ocular or systemic diseases, and congenital cataracts were excluded. Additional information including type of lens opacity, urban/rural region, and pre- and postoperative visual acuities were analyzed. Lens opacity grading was conducted using Lens Opacity Classification System III. The Cochran-Armitage proportion trend test was used to analyze vision changes with the passage of time.
  
  
  RESULTS
  Among the patients who had undergone cataract surgeries, 8.8% (976 / 11,111) met the inclusion criteria. The mean age was 41.7 ± 5.45 years. Gender breakdown of the patient population included 79.0% male and 21.0% female. In terms of home environment, 60.9% were from an urban region and 39.1% from a rural region. Opacity type included anterior polar (AP), posterior subcapsular (PSC), AP and PSC, cortical, and nuclear in 35.7%, 35.1%, 7.0%, 6.0%, and 5.4% of patients, respectively. At a 2-month postoperative follow-up appointment, 92.7% of patients showed a best-corrected visual acuity of more than 20 / 40.
  
  
  CONCLUSIONS
  Predominance of AP and PSC opacities as well as male patients was observed in this study population.
authors.affiliation: Department of Ophthalmology and Visual Science, St. Mary's Hospital, The Catholic University of Korea, College of Medicine, Seoul, Korea.
authors.forename: Hyun Kyung
authors.initials: HK
authors.lastname: Cho
authors.forename: Kyung Sun
authors.initials: KS
authors.lastname: Na
authors.forename: Eun Jung
authors.initials: EJ
authors.lastname: Jun
authors.forename: Sung Kun
authors.initials: SK
authors.lastname: Chung
mesh_terms: D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D002386:Cataract / Q000453:epidemiology* / Q000473:pathology; D002387:Cataract Extraction; D005260:Female; D005544:Forecasting; D006801:Humans; D015994:Incidence; D007903:Lens Capsule, Crystalline / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies
keywords: Anterior polar opacity; Epidemiology; Korea; Posterior subcapsular opacity